Neoclassicism is the style of the late 18th century, of the culminating, revolutionary phase of that great outburst of human inquiry known as the Enlightenment. In its most vital expressions, Neoclassicism sought to bring about a return to primitive simplicity and purity. Dignified, restrained and sometimes rather chilly, it is characterized in the decorative arts by the fondness for simple geometrical forms, the sparing use of Greek and Roman architectural ornament, sobriety of color and a preference for linear and flat, rather than richly sculptural, decoration.

Classical antiquity was imitated as a means to create a style more rational and noble than the earlier delicately light and elegant decorative Rococo style rather than as an end in itself. Though many examples of Greek and Roman furniture were known -- from vase paintings, wall paintings and carvings as well as Roman furniture excavated at Pompeii -- direct copies were remarkably rare before the last decade of the 1700s.

In 1738 the first organized excavation of the ruins of Herculaneum started (and Pompeii in 1748), and with the publication of sumptuously illustrated volumes, architects and furniture designers strove to create ever-more-faithful interpretations of antiquity. Within a few years the "Grecian taste" became a mania: everything was soon in the Grecian style, including exteriors and interiors of buildings, furniture, fabrics and jewelry.

One factor which assisted the rapid development of the new style was the emergence of Rome as a kind of free port for the exchange of artistic ideas. Nearly every artist of any importance in the 18th century spent a few years there studying antiquities and High Renaissance paintings. Rome was also the mecca for the dilettanti of all nations. The education of an English gentleman or German princeling was not complete until he had visited the Eternal City on the Grand Tour developing a taste for the most famous buildings, statues and paintings.

Neoclassicism -- the cult of antiquity -- was more than a romantic nostalgic obsession with the past. It was an enlightened cerebral movement concerned with archeological exactitude. "The only way for us to become great and, if possible, inimitable is through imitation of the ancients," Johann Joachim Winckelmann, Cardinal Albani's librarian, declared in 1764; "The general and predominant mark of Greek masterpieces is noble simplicity and calm grandeur."

This important, if subtle, distinction was recognized by James Madison in his now famous Federalist, number 14 in The Federalist Papers: "Is it not the glory of the people of America that, whilst they have paid a decent regard to the opinions of former times and other nations, they have not suffered a blind veneration for antiquity . . . to overrule the suggestions of their good sense . . . and the lessons of their own experience." These practical Founding Fathers followed the popular maxim: "Reason the guide; Classicism the advisor."

Antiquity haunted the 18th-century imagination. The classical world was the standard of thought and conduct to men of the Enlightenment; it was more real to them than their own world. Ancient history was history in the absolute sense.

The first generation of the American republic saw Greece in the age of Pericles and Augustan Rome as the noblest achievement of free men aspiring to govern themselves. In this conviction they called the upper chamber of the U.S. legislature the Senate, named the new building to house the new government a capitol (not a house of Parliament or a "hotel de ville"), sculpted its heroes in togas, organized the Society of the Cincinnati, assigned Latin texts to the young, and sent them to study at college where the grounds were designated a "campus."

Soon political life was divided into Federalists and Republicans, terms springing from the Latin. And their arts took on a Platonic geometry, in which their architects and craftsmen discerned, as the poet Mark Akenside put it, "In matter's mouldering structures, the pure forms/of Triangle or Circle, Cube or Cone."

Designers and craftsmen in the everyday world of the decorative arts, who abandoned the wayward and frivolous Rococo motifs and responded to demands for greater simplicity, sobriety and solidity by seeking inspiration in Greek and Roman objects, seem to have taken an almost perverse pleasure in transferring motifs from one medium to another. Silversmiths were more ready to take ideas from ancient pottery and marble urns than from Roman silver. Wedgwood derived the form of a soup tureen from an antique marble urn which provided a shape of beautiful simplicity. A pedestal and vase in the Etruscan taste might combine a Roman altar with a Greek vase to provide a decorative object singularly unlike anything ever found in the houses of Herculaneum and Pompeii.

Cabinetmakers resorted to the architecture rather than the furniture of antiquity, and only rarely were chairs and tables copied after antique prototypes until the Empire period. For Neoclassical craftsmen the imitation of the antique was not an end in itself but a means of creating ideal works of universal and eternal validity.

These men saw themselves not as mere Greek or Roman revivalists, but as restorers of the true style. In order to lay bare the truth that lay beneath the surface of nature, they concentrated on form rather than texture, on line rather than color.

Thomas Jefferson's Virginia State Capitol at Richmond was inspired by the little Maison Carre at Nimes, France; but it was far from being a copy (even the classical order was changed from Corinthian to the more chaste Ionic). The Neoclassical architect wished to design in the spirit of the ancients and was ready to invent new orders for new types of buildings -- as Benjamin Latrobe designed his tocacco-leaf and corn-cob capitals for the Nation's Capitol in Washington, D.C.

In the final phase of the Louis XVI style in France during an atmosphere of comparative austerity, a fashion for restrained furniture began to predominate, veneered in the English manner with plain sheets of polished mahogany offset by discreet gilt-bronze or brass mounts.

When Napoleon became Emperor in 1805, he and his consort Josephine became responsible for the decorative style for the whole Empire. Empire forms tended to become more massive in scale and more emphatically rectangular than those of the earlier Directoire. The fashion continued for mahogany and gilt-bronze mounts remained in use especially for more expensive pieces.

Commonly classical figures, often exquisitely cast and burnished, were applied directly to the veneer in low relief. Other favorite motifs included the lyre, the wreath, arrows, the sphinx, amphorae, palmettes and anthemia. Case furniture and pier tables were adorned with pilasters or columns headed by plain Tuscan gilt-bronze capitals, often engine-turned. A common alternative to columns were term figures (a tapering quadrangular pillar adorned with a head or upper body) headed by female masks in either classical or Egyptian garb.

English Neoclassicism can be said to have evolved from the Palladian classicism of Lord Burlington and his circle which preceded it. Robert Adam's furniture designs drew upon the new archaeology discovered in the ruins of Rome. Adam introduced to English furniture design a whole new vocabulary of decorative motifs plundered from antiquity: sphinxes, griffins, caryatids, ox-skulls, rams' heads, putti, medallions, urns, tripods and candelabra found in antique reliefs and wall paintings were rendered in paint, plaster, composition, marquetry and carved wood and linked to a decorative ensemble by trailing and coiling acanthus, paterae and husk swags.

Robert Adam took the total integration of interior design to a level never before seen in England. Furnishings were made to fit into a succession of contrasting spaces planned in the manner of the ancient Roman baths. Ceilings were matched to the specially woven carpets beneath them. The plasterwork filigree grotesques with which Adam lined his interiors were extended into the carving of painted and gilded furniture and echoed in the marquetry of the veneered case pieces so that the whole interior conformed to a uniform decorative style.

The Adam style took England by storm. The influence of Adam on English furniture design is testified to by the pattern books of men such as George Hepplewhite, who first published his Cabinet-Maker and Upholsterer's Guide in 1788. Pattern books of this kind ensured that the types of furniture which graced aristocratic English interiors could be imitated on a less grand scale by American cabinetmakers in the new nation.

The peace treaty of 1782 ended the struggle for independence and marked the beginning of a new era in furniture style in the United States. A desire for change inspired what would eventually come to be called the Federal style. Dated roughly 1785-1810, the Federal period was stylistically rooted in the design and architecture of Britain. Not only did the United States rely heavily on the mother country's art and culture through Hepplewhite and Sheraton's pattern books, many cabinetmakers of the Federal period were themselves, in fact, recent émigrés from Britain and Europe.

Style and design were not the only changes in American furniture following the Revolution. During the Federal era pieces were increasingly embellished using veneers, inlays and exotic woods. Some exceptional pieces were made from bird's-eye maple, satinwood, holly, boxwood, "crotch" mahogany and ebony.

Decorative motifs were crafted into the shapes of shells, flowers or eagles. The eagle, an ancient Roman Republican symbol (and native to North America), was adopted as an American symbol of nationhood.

By 1800, the United States was secure enough as a nation to search for an individual and expressive national style. This young country was attracted by strong feelings of kinship to the ideals of the ancient Greek Republic, as well as by the sophistication of Napoleonic French Empire furniture. French designers who had traveled with Napoleon to Egypt during the campaign of 1798-1802 recorded ancient Egyptian architecture and design. Their pattern books not only influenced French craftsmen, but also were being distributed in the United States. Moreover, the animosity caused by the War of 1812 with Britain had the effect of turning American attention towards French design.

During this late Neoclassical or Empire period more sophisticated construction techniques were employed than before, and a greater variety of different woods (such as rosewood) were used in combination with ormolu, brass inlay, ebony and marble. After 1815 furniture was monumental in proportion and became progressively more heavily sculptured and dramatically carved. At the same time the Greek revival style in architecture spread and became so characteristic of this nation's landscape that America's "tempted hills" were referred to in My Country 'Tis of Thee and our "alabaster cities" immortalized in America the Beautiful.

WENDELL GARRETT is senior vice president of American decorative arts at Sotheby's.